Improvement in lithographic presses



J. GRAWLBY. LITHOGRAPHIG PRESS.

No. 92,276. I Patefited July 6, 1869;

UNITED STATES PATENT OFFICE.

JOHN CRAWLEY, OF BROOKLYN, NEW YORK, ASSIGNOR TO VICTOR E. MAUGER, OF NEW YORK CITY.

IMPROVEMENT lN LITHOGRAPHIC PRESSES.

Specification forming part of Letters Patent No. 92,276, dated July 6, 1869.

To all whom it may concern:

Be it known that I, JOHN URAWLEY, of Brooklyn, in the county of Kings and State of New York, have in vented a new and Improved lt'loistening Attachment to Lithographic Machines; and I do hereby declare thatthe following is a full, clear, and exact description thereof, which will enable others skilled in the art to make and use the same, reference being had to the accompanying drawings, forming part of this specification, in which- Figure 1 represents a vertical transverse section of my improved moistening attachment.

Fig. 2 is a side view of the same. Fig. 3 is a the bottom of the water-reservoir is slotted,

and the water in it is in constant absolute contact with the fabric, which, although it may be more or less compressed, will still always absorb so much water that its pendent lower part will be too freely saturated. The stone is thereby too much wetted, and the printing process consequently delayed and impaired.

My invention consists in-the use of a waterreservoir which is not slotted atthe bottom, but which has one or more apertures through the same, each aperture being provided witha screw-valve. The valves can be screwed down upon their seats more or less, regulate such flow. Thefabric is fastened to the sides of the reservoir and forced together under the apertures to receive the water.

to prevent. the flow of 'water from the reservoir, and will,when opened The invention also consists in the new form of screw-valves, which are grooved or flattened to allow the water to pass constantly through them when not on their seats.

A in the drawings represents the trough, cistern, or other water-reservoir of a lithographic machine. It 'is of semi-cylindrical or other suitable form, supported on a suitable frame.

B B, are the sheets of the absorbing fabric. They are clamped to the converging sides of the vessel A by means of plates a and screws b, or in other suitable manner, so that they come in contact under the middle of the vessel. The bottom of the vessel A has a series of apertures leading through tothe fabric. These aperturesare'provided with internal screwthreads for receiving screw plugs or valves C C. When these valves are screwed down upon their seats they will eflecttmlly close the aperturcs. When raised above the same they will allow water to flow through the apertures to the fabric. The valves are grooved or flattened at the sides, as in Fig. 3, so that water will flow through such grooves or channels when the valves are raised as aforesaid. The flow of water can thus be completely regulatedand the too fast absorption of the same by the fabric and transfer to the 'ston eavoided.

Having thusdescribed my invention. what I claim as new, and desire to secure by Letters;

Patent, is-

1. The water-reservoir A, when provided with apertures for receiving the screw-valves C and with the converging sheets of absorbing material, substantially as herein shown and described, to operate as set forth.'

2. The screw-valves C, applied to the moist.- ening attachment herein described, when grooved or flattened, substantially as and for the purpose specified.

JOHN CRAWLEY.

Witnesses FRANK BLOCKLEY, O. L. TOPLIFF. 

